二维斑点追踪成像评价尿毒症患者左室心肌分层应变

Evaluation on left ventricular myocardial stratified strain in uremia patients by two-dimensional speckle tracking imaging

目的应用二维斑点追踪成像(2D-STI)技术评价尿毒症患者左室心肌分层应变情况。方法选取我院经临床和病理检查确诊的尿毒症患者60例(病例组),另选同期60例健康志愿者为对照组。常规超声心动图检测左室舒张末期容积(LVEDV)、左室收缩末期容积(LVESV)、舒张末期左室后壁厚度(LVPW)、舒张末期室间隔厚度(IVS)及左室射血分数(LVEF);分层应变技术测量左室两腔、三腔及四腔心切面心内膜下、中层、心外膜下层心肌的纵向应变峰值(LS)、圆周应变峰值(CS)及各个切面心肌整体纵向、环向分层应变的平均值(GLS、GCS),计算各个应变之间的差值,得到左室各层心肌整体纵向、环向分层应变跨壁应变梯度(△GLS、△GCS),比较两组上述参数差异。结果两组LVEDV、LVESV、LVPW、IVS及LVEF比较差异均无统计学意义。两组左室心肌GLS均表现为心内膜下心肌峰值最大,且由内至外逐层递减,两组比较差异有统计学意义(P<0.05);病例组左室各层心肌GLS及△GLS均较对照组对应各层心肌有所减低,差异均有统计学意义(均P<0.05);两组间基底段、中间段及心尖段CS、GCS及△GCS比较差异均无统计学意义。结论尿毒症患者在LVEF降低之前就已存在左室心肌与收缩功能的损伤,全层心肌的收缩功能均有不同程度的降低,其中以心内膜下心肌功能受损最为严重。STI可评价尿毒症患者左室心肌分层应变。

Objective To evaluate the left ventricular myocardial stratification strain in uremic patients by two-dimensional speckle tracking imaging(STI)technique.MethodsSixty uremic patients who comfired by clinical and pathologicalexamination and 60 healthy volunteers were enrolled in,and they were divided into the case group and the control group.The leftventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV),left ventricular end diastolicposterior wall thickness(LVPW)and interventricular septal thickness(IVS)and left ventricular ejection fraction(LVEF)weremeasured by two-dimensional echocardiography.The longitudinal strain peaks(LS),circumferential strain peaks(CS),and theaverage value of hoop stratified strain(GLS,GCS) were assessed at endocardium,mid-myocardium and epicardium weremeasured by stratified strain technique in the left ventricular two-chamber,three-chamber and four-chamber cardiac sections.The difference between each strain to obtain the overall longitudinal and hoop stratified strain across the wall strain gradient(△GLS,△GCS)of the left ventricle were calculated.ResultsNo significant difference of LVEDV,LVESV,LVPW,IVSand LVEF between two groups was found.The GLS of left ventricular myocardium in both groups decreased from endocardiumto epicardium,and signifcantly increased from basal to apical segment(P<0.05).The GLS and △GLS of each layer of two-chamber,three-chamber and four-chamber cardiac sections in the case group were lower than those in the control group(allP<0.05).There was no significant difference in CS,GCS and △GCS of basal,middle and apical segments between the two groups.ConclusionIn patients with uremia,the left ventricular myocardium and systolic function had been damaged before the LVEFis reduced. The systolic function of the whole layer of myocardium is reduced to varying degrees,and the subendocardialmyocardial function is most severely damaged. STI can sensitively reflect the changes of left ventricular systolic function inpatients with uremia.